Training

The Myths of Sports Nutrition

The Athlete’s Kitchen

Copyright: Nancy Clark MS RD CSSD Feb 2014

Sports Nutrition: What’s Old? What’s New?

Once upon a time, warriors (the original athletes) ate lions’ hearts. Today, athletes seek out energy drinks and protein shakes. Clearly, times have changed! In case you are wondering what else is old—and new—when it comes to sports nutrition, I’ve compiled an update to help resolve confusion so you can fuel for success.

OLD: The lighter you are, the better you will perform.

NEW: The runner who is genetically lean and eats enough to have well-fueled muscles has an advantage over the runner who is genetically heavier and has to skimp on food to maintain an unnaturally low weight. Research with elite female swimmers indicates those who restricted calories in the pursuit of thinness lost speed (but not body fat) during a 12-week training cycle, while those who ate adequately swam faster (1). Thin at any cost often comes with a high price tag.

NEW: Lack of fuel, not lack of body fat, tends to determine if a female runner’s body will menstruate normally. That is, many very lean female runners do have regular menses. Although they may have very low body fat, they eat enough to support both their exercise and normal body functions.

OLD: Eat fat, get fat.

NEW: Yes, excess calories of dietary fat can easily convert into body fat. But healthful fats (i.e., nuts, olive oil, avocado, salmon) are an important part of a runner’s diet; they help reduce inflammation. Runners also need dietary fat to absorb important vitamins such as A, D, E, and K. Fat also fuels the muscles; small amounts of fat get stored within the muscles and can enhance stamina and endurance. Research suggests runners had more endurance when they switched from a very low fat to a moderate fat diet. (2)

OLD: If you want to lose weight, you need to go on a diet.

NEW: Diets do not work. If diets did work, then everyone who has ever been on a diet would be lean. Not the case. Rather than going on a diet, try to make just a few basic changes, such as 1) choose fewer processed snacks in wrappers and instead enjoy more fruit (fresh or dried) and nuts, and 2) get more sleep. Lack of sleep can contribute to not only weight gain but also reduced performance.

OLD: The recommended dietary allowance for protein (RDA) is the same for runners as for non-athletes.

NEW: The RDA for protein (0.8 grams per kilogram body weight.) is less than the 1.2 to 1.7 g pro/kg currently recommended for athletes. Most runners eat that much (plus more) as a part of their standard meals, so you are unlikely to need protein supplements. You do want to distribute your protein intake evenly throughout the day, and not pile it all into dinner, so your muscles have a consistent supply of amino acids (the building blocks of protein).

OLD: Slabs of roast beef help build bigger muscles.

NEW: Because the body can utilize only about 20 to 25 grams of protein at one dose, you won’t build bigger muscles by eating jumbo portions of beef in one sitting. (4) Your better bet it to cut that slab of meat into four pieces. Enjoy those deck-of-cards-sized pieces at least every four hours, so you get 20 to 25 grams of protein at each meal and afternoon or evening snack. Weight lifting—not eating excessive protein—triggers muscles to grow bigger. To have the energy needed to lift heavy weight, you want to eat meals based on grains, fruits and veggies (with protein as the accompaniment). Those carbs provide the fuel needed to lift heavy weights.

OLD: Don’t drink coffee before running in the heat; it is dehydrating.

NEW: Pre-exercise coffee is not dehydrating and it can actually enhance performance, even in the heat (5). Caffeine boosts alertness and reaction time, as well as makes the effort seem easier so you work harder without feeling the extra effort. If you are sensitive to caffeine (a mugful gives you a “coffee stomach” and the jitters), you’ll be better of abstaining. But runners who enjoy drinking coffee are likely to notice positive benefits.

OLD: Energy drinks contain magical ingredients, such as taurine.

NEW: The magical ingredients in energy drinks are caffeine and sugar. Although taurine has been reported to enhance performance, the limited research was done on rats. Newer research suggests taurine offers no ergogenic benefits (6). To save money, simply add a heaping tablespoon of sugar to your coffee. You'll get the same boost. Better yet, eat wisely and sleep more; you won't need an energy drink…

OLD: Don’t eat before you run. The food just sits in the stomach and does not get digested.

NEW: You can digest food during a run as long as you are exercising at a pace you can maintain for more than 30 minutes. Fitness runners can benefit from a small pre-exercise snack as tolerated (such as a banana, granola bar, or packet of oatmeal) to get their blood sugar on the upswing. Marathoners who run for more than 90 minutes will benefit from both pre-run fuel and then carbs during the extended workout. The target is about 250 to 350 calories of carbohydrates per hour. That’s more than just a swig of sports drink! Be sure to practice fueling prior to and during long runs, so you can learn what works and what doesn’t.

OLD: Refuel as soon as possible after you workout.

NEW: If you do exhausting workouts twice a day, you’ll benefit from eating soon after the first run to fuel-up for the next run. But if you are a fitness exerciser, simply back your workout into the next meal. You’ll have plenty of time to recover before your run the next day.

OLD: Orange slices are perfect for half-time of a youth sporting event.

NEW: While chomps, gels, and sports drinks may seem better than cut-up oranges and water for half-time fueling at youth sports events, kids actually should be taught that natural foods work well. Orange slices, pretzels, and water provide more nutrients and electrolytes (a.k.a sodium and potassium) than sports drinks. Even adult runners can do well with real foods. While elite runners might prefer engineered products during intense exercise, most of us can perform just fine with real food. Go back to enjoying more orange slices, please. Sometimes the old ways can be preferable to the new!

Boston-area sports nutritionist Nancy Clark, MS, RD counsels both casual and competitive athletes. Her private practice is in Newton, MA; 617-795-1875. For information about her new Sports Nutrition Guidebook, 5th Edition, and her food guides for runners, cyclists and soccer players, see www.nancyclarkrd.com. For online education, visitwww.sportsnutritionworkshop.com.